#17476: make allmethods actually return all methods.

This fixes a regression relative to Python2.  (In 2, methods on a class were
unbound methods and matched the inspect queries being done, in 3 they are just
functions and so were missed).

This is an undocumented function that pydoc itself does not use, but
I found that numpy at least uses it in its documentation generator.

Original patch by Matt Bachmann.
#17460 - Adding relevant warning messages regarding strict removal in docs
Fix usage of the unittest.skip decorator.
#17443: Fix buffering in IMAP4_stream.

In Python2 Popen uses *FILE objects, which wind up buffering even though
subprocess defaults to no buffering.  In Python3, subprocess streams really
are unbuffered by default, but the imaplib code assumes read is buffered.  This
patch uses the default buffer size from the io module to get buffered streams
from Popen.

Much debugging work and patch by Diane Trout.

The imap protocol is too complicated to write a test for this simple
change with our current level of test infrastructure.
#8862: Fix curses cleanup with getchar is interrupted by a signal.

I have no idea how one would write a test for this.

Patch by July Tikhonov.
#17471 - Improve urllib2 test coverage. Patch contributed by Daniel Wozniak